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After lots of glowing recommendations, I decided to buy a Technical Innovations Robofocus for my Explore Scientific ED127 telescope and its stock Crayford focuser. Together with my astrophotography computer and camera, this should let my scope automatically focus itself with much better accuracy than I ever could.

I dug through their website, but didn’t see an Explore Scientific installation example and I couldn’t find one after quite a few online searches either.

I sent Technical Innovations an email asking if the Robofocus would fit my scope. They replied back asking for a photo of the bottom of my scope’s focuser and the diameter of the focus knob shaft (it’s 0.158″ on the single-knob side). After sending that info, they told me they could send a Robofocus with brackets that would work.

A few days after ordering, my Robofocus showed up. They sent two identical mounting brackets. With probably thousands of possible focusers out there, the Robofocus manual didn’t have specific installation text or photos for my scope. I did a little more searching online and still didn’t find an example of a Robofocus/Explore Scientific ED127 combo. So, I dove in.

There doesn’t appear to be a “perfect” place to anchor the mounting bracket on my existing focuser. The best place with existing bolt holes looks like the bottom of the focus knob assembly. I took off the single-knob and slipped the Robofocus into place. A couple of bends later, the once-flat mounting bracket fit flush to the bottom of the focus knob assembly and the Robofocus’ mounting holes.

Here’s the bent mounting bracket.

Here’s the bracket & Robofocus in place on the scope.

The only down side to this mounting bracket location is that the bolt on the bottom of the focus knob assembly is really small. Technical Innovations says in their FAQ that you can attach the mount to the scope using “Very High Bond” tape. 3M makes Very High Bond (VHB) tape that should work. I’ve also heard of several people using 3M’s Command brand of double sided tape. This tape is commonly used to hang hooks on walls, doors and other similar applications. Since 3M Command tape is available almost everywhere, I’ll try that first. I probably have some in the garage…

I haven’t done any official research, but my guess is amateur astronomy buffs spend most of their astronomy time in their backyards. Home-based astronomy is great because it’s “right there.” It’s easy to set up your telescope and view the planets, moon, and maybe even some darker deep space objects like galaxies and nebulae.

One of the bad parts about backyard astronomy is light pollution. NASA recently published images of the entire world’s “light map” taken at night from space. If you live in the US, odds are you live in one of the bright areas of the image below.

In general, those bright spots are concentrations of people. For some crazy reason, people like things like street lights. Those street lights wreck havoc on the darkness of the night sky. When I was young, we lived outside town far enough that I spent many mornings admiring the stars while waiting for the school bus. I used to imagine what each star was like and wondered if anyone else was out there. In many cities, only a few stars are ever visible to the naked eye. That definitely makes it tough to be inspired by the night sky.

Just recently, my neighborhood replaced all of the halogen street lights with LEDs. Their goal was to save money on electricity. A great side benefit was the light pollution near my home dropped quite a bit. I still have the glowing fireball of Las Vegas to the north of my home, but the skies are fairly dark to the south.

I have to admit that, despite living in my home for over 3 years, I’ve never done any astrophotography from my backyard. I assumed that because I lived in a big town, it wouldn’t be worth the effort. Turns out, I was wrong.

Two nights ago I dragged out the telescope, cameras, laptop, tables, power cords, and piles of USB cables. I did a quick polar alignment using my Celestron CGEM’s built-in polar star alignment routine. I centered the scope on the Orion Nebula and started shooting photos. The skies were dark enough that my camera was able to capture up to 5 minute exposures without being too blown out from the light pollution.

Over a couple hours, I took a total of 25 shots of the Orion Nebula ranging from 30 seconds to 5 minutes each. I crunched all the data yesterday and ended up with a backyard astrophoto that I’m happy with. Here’s the result (click on the photo to see the full sized version).

So, what do you think? I think you should go outside and look at the stars. Find Orion. It’s just south of “straight up” at about 8pm. Try to find the Orion Nebula. It’s the jewel in Orion’s sword. There it is.

Pete Mumbower has an outstanding idea for making a Celestron CGEM mount easier to polar align. He adds “Slick Strips” to the top of the tripod where the mount rests. This makes tweaking the alignment of the mount much easier. My Slick Strips are on order!

I just got back from a dark-sky trip to Mahogany Flat Campground in Death Valley National Monument. I captured this image of the recently discovered supernova in Messier 101.

Click the photo for the full resolution version.

The image was taken with an unmodified Canon 5D Mark II through a Celestron 80ED refractor mounted piggyback on a C8 on a CGEM mount. I took 12 exposures each 5 minutes long for this shot. I combined & processed them using Nebulosity. I haven’t taken the time to get a magnitude from this photo, but comparing it to earlier photos, the supernova is definitely getting brighter very quickly.

For several years, my Celestron telescope’s NexStar hand controller has been getting fussier & fussier. On my last dark sky trip (many hours from home), the hand controller stopped responding. I messed with it in the field for about 5 hours that night…cycling power, attempting realignments, etc. Nothing worked. The one time that night I got the scope’s computer to align, the hand controller stopped responding as soon as I sent it to my first target.

I spoke with Celestron about it and their best suggestion was to send back the entire mount so that they could work on it. Their estimate to just look at it was $200. They did tell me that the first thing they’d try was a new hand controller. So, instead of sending in the telescope, I tried to order a new hand controller. Except for places I didn’t want to order from, everyone was out of stock. Months went by. No hand controllers.

Fed up, I started digging around the internet again for a solution. I found a post where several people had similar problems. I tried their solution and it worked! It looks like the LCD ribbon cable works loose in the Celestron hand controller. I took apart the hand controller (just 6 screws), pulled back the two tiny black ribbon locks, then removed the LCD ribbon. The contacts were dirty, so I used some non-residue electrical contact cleaner and a cotton swab to clean them up.

I put everything back together and the scope fired up and aligned without a hitch. I’ll drag it out at night next weekend to give it a good checkout. Hopefully, this 10 minute fix saved me $150.

You wouldn’t think that an LCD ribbon would mess up the mount’s ability to slew around & receive commands from my laptop. Still, it looks like they might be related.